Why are fingertips wet with saliva before counting money?

What is the empirical formula of vanadium 1 oxide given that 20.38 grams of vandium combines with oxygen to form 23.58 grams of the oxide

Apiece of copper has a temperature of 75.6 0c. when the metal is placed in 100.0 grams of water at 19.1 0c, the temperature rises by 5.5 0c. what is the mass of the metal?

Which of your 24 wells had indications that a chemical reaction occurred? how were you able to tell that a chemical reaction occurred? which of your 24 wells had indications that a physical reaction occurred? how were you able to tell that a physical reaction occurred? report on both mixing and evaporation. make a general statement about whether your hypotheses were validated or rejected. must your hypotheses be correct for this to be a successful laboratory?